Added example usage code.

README.md

@@ -6,6 +6,77 @@ It will map the models/fields to internal GraphQL-py objects without effort.
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+## Usage
+
+Example code of a GraphQL schema using Graphene:
+
+### Schema definition
+
+```python
+import graphene
+# ...
+
+class Character(graphene.Interface):
+    id = graphene.IDField()
+    name = graphene.StringField()
+    friends = graphene.ListField(graphene.Field('self'))
+    appearsIn = graphene.ListField(Episode)
+
+    def resolve_friends(self, args, *_):
+        return [wrap_character(getCharacter(f)) for f in self.instance.friends]
+
+class Human(Character):
+    homePlanet = graphene.StringField()
+
+
+class Droid(Character):
+    primaryFunction = graphene.StringField()
+
+
+class Query(graphene.ObjectType):
+    hero = graphene.Field(Character,
+        episode = graphene.Argument(Episode)
+    )
+    human = graphene.Field(Human,
+        id = graphene.Argument(graphene.String)
+    )
+    droid = graphene.Field(Droid,
+        id = graphene.Argument(graphene.String)
+    )
+
+    @resolve_only_args
+    def resolve_hero(self, episode):
+        return wrap_character(getHero(episode))
+
+    @resolve_only_args
+    def resolve_human(self, id):
+        return wrap_character(getHuman(id))
+        if human:
+            return Human(human)
+
+    @resolve_only_args
+    def resolve_droid(self, id):
+        return wrap_character(getDroid(id))
+
+
+Schema = graphene.Schema(query=Query)
+```
+
+### Querying
+
+Querying `graphene.Schema` is as simple as:
+
+```python
+query = '''
+    query HeroNameQuery {
+      hero {
+        name
+      }
+    }
+'''
+result = Schema.execute(query)
+```
+
 ## Contributing
 
 After cloning this repo, ensure dependencies are installed by running: